Biomedical subjects

O Hjalmarson

Publications and source records attributed to O Hjalmarson.

36 records · Page 2Linked to original sources

PubMed1986

Interval from rupture of the membranes to delivery and neonatal respiratory adaptation.

The influence of the time interval from rupture of the membranes to delivery on neonatal respiratory adaptation was analysed in a prospective study of all infants born in Göteborg, Sweden in one year. The correlation between the incidence of respiratory disorders and the rupture-delivery interval was analysed in all preterm infants (less than or equal to 36 weeks, n = 240) and in all term infants born by caesarean section (n = 452). A uniform pattern was found for all preterm infants, irrespective of mode of delivery, and for the term infants born by caesarean section. The curve was 'U-shaped' with higher incidence of respiratory diseases in infants born immediately after rupture of the membranes than in those born 3-36 h after membrane rupture. The incidence increased again in infants born greater than 36 h after membrane rupture. The same pattern was found for all kinds of respiratory diseases including idiopathic respiratory distress syndrome. Therefore, there seems to be no advantage in postponing delivery greater than 36 h after rupture of the membranes.

Cesarean Section↗

PubMed1984

Long-term follow-up of infants under intensive care with tracheotomy during the period 1956-1965.

Twenty-seven infants who survived intensive care during early infancy in the pioneering period of neonatal intensive care (1956-1965) were investigated after 8-17 years. The selection criterion was maintenance of a tracheotomy for more than 15 days during the first 12 months of life. A variety of clinical, physiological, radiological and psychiatric sequelae was found. Respiratory symptoms were the dominating problem during the post-tracheotomy period. The long-term follow-up revealed that these symptoms had a strong tendency to subside. At the time of the follow-up, as many as 20 children (74%) did not experience any functional impairment.

Child Development↗

PubMed1984

Analysis of alveolar ventilation in the newborn.

Twelve healthy term infants were examined at the median ages of 2 1/2 and 26 hours. Their alveolar ventilation, efficiency of ventilation, functional residual capacity, and lung nitrogen elimination patterns were studied by means of a computerised nitrogen wash out method. The results showed that alveolar ventilation and functional residual capacity increased over the period studied. At the same time effective dead space decreased leaving minute ventilation unchanged. Distribution of ventilation did not change.

Aging↗

PubMed1984

Calculation of lung volume in newborn infants by means of a computer-assisted nitrogen washout method.

A clinically adapted method for the calculation of the functional residual capacity in newborn infants has been developed. The method is based on a multiple breath nitrogen washout test, during which the ventilatory air flow and the nitrogen concentration signals are sampled by a minicomputer, which also performs the calculations. The ventilatory air flow is measured by a pneumotachometer connected to a face-out volume displacement body plethysmograph, and the nitrogen concentration by a nitrogen analyzer. The functional residual capacity volume is calculated from the sampled signals by adding the expired nitrogen volumes during each expiration, and finally dividing this sum by the initial alveolar nitrogen concentration. Before the calculations, the sampled signals are adjusted regarding nitrogen analyzer delay and plethysmograph characteristics. The method presented is designed to minimize the test equipment influence on the baby's respiration and also to inhibit the necessity of pneumotachometer compensations normally connected with washout methods. Furthermore, the calculated breath-by-breath values of end-expiratory nitrogen concentration, nitrogen volume, inspired and expired tidal volume, are stored on disk for further analysis and resimulation of the test. The method has been tested on a mechanical lung model and on washouts from healthy newborn infants. The model tests indicate that the accuracy and the reproducibility of the method are good, and the results from the infants are in good agreement with previously obtained results.

Computers↗

PubMed1983

3-Methylglutaconic aciduria in two infants.

We studied two children who developed normally for the first 3-4 months of life and then displayed a failure-to-thrive syndrome, regression in psychomotor development, pronounced muscular hypotonia, and liver damage. At the age of about 1-2 years, optic atrophy and spastic parapareses were evident. One child died at the age of 2.5 years the other at an age of 4 years. Both children excreted 3-methylglutaconic acid, 0.1-0.4 mol/mol creatinine and 3-methylglutaric acid, 0.02-0.05 mol/mol creatinine. The excretion of 3-hydroxy-3-methylglutaric acid was not increased. One of the children was available for further biochemical studies. The activity of hydroxymethylglutaryl-CoA lyase (EC 4.1.3.4) was moderately reduced in leucocytes and fibroblasts. During a 21-h fast there was a normal formation of ketone bodies and we conclude that the cause of the syndrome is not a deficiency of hydroxymethylglutaryl-CoA lyase. Normal formation of 14CO2 from [1-14C]isovaleric acid and [2-14C]leucine in fibroblasts and leucocytes apparently excludes a deficiency of methylglutaconyl CoA-hydratase (EC 4.2.1.18).

Creatinine↗

PubMed1982

The effect of chlorpromazine in severe hypoxia in newborn infants.

Eighteen newborn infants with severe hypoxia during the course of idiopathic respiratory distress syndrome, pneumonia, persistent fetal circulation or right diaphragmatic hernia were treated with chlorpromazine with the aim of improving arterial oxygenation by a postulated vasodilatory action on the pulmonary circulation. Fourteen of the infants improved their PaO2 during the treatment. Nine infants died. The systemic arterial blood-pressure and the urinary output were reduced and some infants were somnolent during the initial period of treatment. No other side effects were noted. Further studies of chlorpromazine as a possible pulmonary vasodilator in newborn infants are justified.

Chlorpromazine↗

PubMed1982

The importance of neonatal asphyxia and caesarean section as risk factors for neonatal respiratory disorders in an unselected population.

The risk of neonatal respiratory disorders was calculated in an unselected, total population together with the relative contributions of some factors found associated with an increased risk. Postnatal asphyxia, expressed as a low one minute Apgar score, and low gestational age were substantially, independent risk factors. Caesarean section added, though less markedly, to the risk of the above disorders.

Apgar Score↗

PubMed1981

Epidemiology and classification of acute, neonatal respiratory disorders. A prospective study.

In a prospective study a population of 32 281 newborn infants in Sweden was screened for signs of respiratory disease. All affected infants (2.9%) were investigated systematically and classified. Incidence and case fatality rates were calculated and related to gestational age, birth weight, sex and postnatal asphyxia, all of which strongly influenced one or both rates. The diagnostic system used was found suitable for future epidemiological research.

Asphyxia Neonatorum↗

PubMed1978

Bilateral renal asplasia without Potter's syndrome.

A newborn infant with bilateral aplasia of kidneys and ureters and a rudimentary bladder is reported. Other manifestations of Potter's syndrome (oligohydramnios, lung hypoplasia and an abnormal face) were missing as were other congenital malformations. Deviations from the full picture of Potter's syndrome seem to be rare. This case, however, shows that bilateral renal aplasia cannot be excluded as a cause of anuria in a newborn infant, even if all other manifestations of Potter's syndrome are missing.

Abnormalities, Multiple↗

PubMed1977